s7- can't perform factory hard reset

[AC Question]

Hello everyone
I bought a second hand s7 but it has some software problems:
1 i cant update simple apps becouse it says that thers insufficient storage.
2: when i check the storage it says i still have 7 gb free, its a 64 gb s7 so it seems strange that 58 gb are occupied by firmware bit even with 7 gb is enaugh for updates of youtube and whatsapp so the problem 1 is strange.
3. when i tried to hard reset it the picture is inverted ( i have to turn my phone 180 degrees in order to read whats written which is weird) , i can use the volume up arrow to choose the mode but when i press volume down button to confirm the choice it doesnt do anything. Its not a button problem becouse it works perfectly when the phone is turned on.

I wanted to flash it but even for that i need to enter download mode, which i cant becouse the phone doesnt respond.

i would like some advise from experienced samsung users becouse im afraid on bricking it or making it stuck in bootloop.

 

[anon(238680)]

Welcome to the forums. I am not the person to help much, but something first. Do you know that the Google account of the previous owner was removed? If not, and you reset, you'll need that sign in. Just a caution, see posts here all the time from people who got caught in that. Also, look over these:

How to flash Stock ROM via ODIN with the New Interface:
https://forums.androidcentral.com/a...w-flash-stock-rom-via-odin-new-interface.html

Download and flash using Smartswitch:
https://www.youtube.com/watch?v=9QhJngOuLQ4

If you need additional help or have more questions or details to share, please join the site so you can reply in this thread. See this link for instructions on how to join Android Central.

 

[anon(238680)]

Mod Note: Thread moved for better visibility.

 

[glorveth]

I'm in contact with the previous owner so i think he'll give it to me in case of need, plus ive already logged in with my gmail.
i already know how to flash having flashed an s5 , i just cant enter the download mode in the first place , also i would like to format it first to avoid the bootloop risk. The full memory issue is making me doubt becouse all guides on rooting say to check if enaugh space is aviable for the new firmware.
all in all i want to be sure on what im doing becouse s7 are more expensive then s5s and i cant afford to brick this phone.
Thank you a lot for the fast answer and moving the thread

 

[CWinkler]

when i tried to hard reset it the picture is inverted ( i have to turn my phone 180 degrees in order to read whats written which is weird) , i can use the volume up arrow to choose the mode but when i press volume down button to confirm the choice it doesnt do anything. Its not a button problem becouse it works perfectly when the phone is turned on.

If memory serves me correctly, it's the POWER button to confirm your choice, not volume down. Might that help?